Water heater



Feb. 19, 1935, o. JoHNsoN WATER HEATER med Feb. e, 193s Patented Feb`.f19, 1935 -j f cm1-'Eo QFFICE 9 external Water coil.

Application February 6.

1933, Serial No. 655,310.

` .7 Claimg. (Cl. ige-.14)

VThis .invention relatesl to-"water heaters of the type lwherein the water is heated in awater coil.

by a gas or other flame, usually thermostatically controlled and the heated water isl stored in an insulated'sto-ragetank:r Y v y f .An object ofthe present inventionis to improve the eidcieney of water heatersv of` this'l type byV locating the Vwater coil in aheat-.conducting tube that" is disposedwithin the tank and in intimate heat-transferring relation with the heatingflame and with the stored water so thatgthe ame not only heats the water in thewater coilbut, also directly heats the water in the tank whereby con@ siderably more heat can be abstracted from the flame than with the usual heater, having `an A further object ofthe present invention is in the provision of' a llame-controlled damper in the top of thercoilfcontaining tube and so ar. ranged that when the Iianie is out, it substantially closes the outlet of the tube and thus prevents the cooling of the tube and the water by. cool air that would otherwise flow up the tube by natural draft, the damper also being so arranged that it automatically opens in response to the buoyancy of the heated gas under it-in the tube, when the flame is burningand so provides an exhaust opening for the gases. The damper is arranged, however, to. throttle the hot gases so that they have time to give up mostof their heat to the tube and the water coil before escaping from the tube; .j v

A further object is generally to improve the con; struction and performance of water heaters.

Fig. 1 is a sectional elevation through a water heater'embodying thecpresent invention. Y

' Fig. 2 is an enlarged sectional elevation of the automatic damper of Fig. 1.

.ing thepresent inventioncomprises a vertical wa-V -ter storage tankvl'. havingla cylindrical shell 12, a'

tonneau .1a. anda bottom head 1e.v 'cold water :enters ,through apipe 118 and hot water' is with- Adrawrrfthroug'h.a pipeZp. The water in the'tank Vis Ausually Vunderthe pressure of the water system rto which 'the inlet pipe '1*8 is connected. The

tank is enclosed within a vsuitable heat-insulating @casing comprising a vertical cylindrical shell 22,

lanlupperhead 24, and/allower supporting plate .or washer 26vupon whichth'e' tank lllissupported..

The space between the heatV insulating casing and the tank.` @meins a .Suitable heat-insulatirlg mediu'h1n'28.r The outer shell 22 extends below the washer 2,6v and is secured to suitable supporting legs` 30 which have shelves 3.2 at their upper ends upon which saidwasher is supported. The lower 5 portion of theshell, below said washer, is`pro` vided with a door 34 by whichaccess may be had to Va burner 36, here shown asa gas burner,k located` under the bot/tom head of the water tank and suppliedby gas bya pipe 38, the owof- 10 gas through whichj is automatically controlled by a' thermoresporisivefdevice.4Q immersed in the vwater in the lower part of the storagetank.' A

gaspilot 12, continueusly burning, servesv to igniteV 1 thegasatthe burner when the ges id turned GHI 1.5

' by theoperation .O f 'the thermoresponsive device in response to a lower water temperature. AV dripV plate 44 is located under the burner and serves toV `Ycatch anyfeondensate that may forni as a result vof theburning gas. c peripherally spaced from the* outer shell A22 so as toprovide sucient airffor the combuetion of .thegafS--.. ,In accordance with this invention the water tank 10Y is provided with a, relatively'large 2 5 diameter .metal tubeAG.: that .extends axially through l .the tank and .thejupper and lower heads 14 and 16 thereof and is secured in aV pressureftight manner therewith, the heads having arriallyfextencled necks 47 whichclose- 30 ly s lfirrolfind and engaglsaid tube -and are` rveted,' -welded or otherwise kconnected therewith. The upper end o f the tube extends through and is terminated atthe top of avneck 2,5;of thetop head 24. of the insulating-casing. Ijhe A35 .burner-3691s disposed immediately.' under the lower open end of said tube so that the llame issuing Y therefrom is caused to` pass upwardly .withinrthe tube. u The diameter of the tube preferably is about four-tenths or `five-tenths of that 10 of the water tank or the shell 12 thereof and so hasa Alarge area'of surface'in contact withv the 4watchin tank. The tube is of suitable thickf rness to resist the vpressurelin the tank. The

waterin the tank isfinintimate contact andheat- 45 exchanging relation'with the outer surface of 4' the tube. A watercoil48, consisting of along length of pipe'ortube, wound in a succession of aniallyfclcsely-,spaced convolutions .of dierent Thelower en d Y5.0 of the coil is xed to the lower u part IOLthetuheand is opentherethrough to the A:Etaid plate is 240 I so that efcient heating of Y i and the large surface area of the tube greatly`A e while providing a free gas passage 36-is adapted to flow.

`said opening is controlledby a dampercompris- .diametrical line -of the disc, say

bottom part of the water'space inthe tank and the upper end 52 of the coil is similarly connected to the upper part of the tube and is open tothe top part of the water space in the tank. The flame from the burner 36 passes upwardly through the tube 46 and around and through the coil 48 and between the convolutions thereof and so directly heats the water in the coil and also in the tank. y l n e With this arrangement the gas is rin intimate contact on all sides with water heating surfaces increases the total heat-transmitting area. `V'If-he tube 46 causes the water in the tank to be heated directly and the water in the tankiscaused to circulate between the top and'bottomthereor and thereby to break up the stratification loetween the hot and cold bodies by the coil 48. Hence, practically all of the water in the tank is at the same temperature .and thus the present tank Vcan -hold a 'greater quantity of hot water, before thefthermoresponsive device shuts voff therrlama'thanv itheV Water washeated by an external waterfcoil.v The efficiency of .the heater is further enhanced by a iiamecontrolled damper which, y through the tube46 when needed, normally operates togplace the heatedgases in the tube under sornecpressureV and to hold the gases in contact with theftube andthe water coillong enough forVY the gases to give up almost all of their availableheat to the water. Said damper includes a damper support in the form ofy a cup 54 Vhavinga cylindrical side wall 56,- a horizontal bottom wall 58 which has aV-diameterfabout equal to that of vthe tube 46, and` an oustanding 'flange 60Vat itsupper end. Y located intheupper end of the tube 46 and supported removably therein bythe ilange 602 which isseated upon the. upper end of the tube, the depth of the vcup` preferably be.- ing suchthat the bottom wall is disposed about in the plane of the top head 14 of the `water tank. The cup thus forms aclo'sure for the top of the tube. The bottom wall 58 ofthe Vcupmhas a circular opening 62 therein'of relatively large diameter through which the gas from the burner The flow' ofgas through ing a generally circular plate or Vdiscf64`which is secured to the underside of a shaft 66 pivoted at its ends in bearings 68 carried by thebottom wall of the cup. Theshaft lisloffset" from the about Vhalfway betweenthe center and the edge thereof, sothat the disc is provided with two sections volf unequal area the portion 64o beinglarge and the portion` 64bY being small in area and the portion 64ctoverbalancingA the weight of the portion 64b. The portion 64a overliesthe opening 62 and seats upon the wall 58and the portion 64b is of such reduced diameter that it can swing throughsaid opening 62 when thedisc -pivots about its shaft bearings 68. A counterbalancing mass '70y is carried by the part 64b and has such weight as almost to balance the excess weight of the part 64a oi the damper, say within half an ounce. p Hence the damperis normally closed and ythe 'only passage for gas is vthrough the clearance space between thel part 64b of the damper and' the jside wall of the opening 64, which is suicient to ventilate the tube of the gasesof the pilot 42. When the burner 36 is'in operation, however, the pressure or buoythe water is obtained, :relieve any pressure devloped'in the tubevs; Q.'

mixture in the tube'. Y voif andthe flame goes out, the da of water caused f' Ymunication fwith the removable plate locatediin zontally across l l Vhaving an `opening therethrough, adamperr-lec- .vidingga 'seat whichgsupport said Yplate ,removably ancy of the heated gases oil thef'damper causes the damper te uit upwsfa1yv-asindmated by the dotted Alines, Fig'. 2. amatuer-ew uncover me opening' 64 and pei-Init I the gases to' escape, aniuiit of, opening of the damper s Th that 1 the' heatedy gases are under some pressure in the to the ywater' in' me 0011,43' rrii 'Contact with ,1

result of an exploslve combustion-6fth gaseous;

'whenthebunfe A smit .pef blogs' and prevents the'natural draftfrompassin'g acurf: Y rent ofkcool airthrough the tube'rnid cooling' off 'the heated 'waterlA 'The closed dairper 'aleb keeps in the warmfc'ombustion gases'fr`iv`gn` ;the"` continuously burning pilot; and ithas found institue pilot `riannethough Smau/wim the closed damper, assists materially in keeping@ the vvater'hotr; v 1 '1 YAn' Lopen-'ended' cylindrical shell v"72 is -seated uponV the top head 240i the insulating casing,

around the 'open/end of vthe-tube 46, aridY has a Y lateral connection" with a chimney i pipe 74 through'whichthe products of combustionare' exhausted. l `The open by a heat-insulated cover able and, vwhen-it andthe e moved, provides free access to the interior ofV thev tube ifi'andV to the Watercoil 48 for cleaning: purposes.l

'76 'which is remov-V ri'ests on a heater constructed asl above'de-l 3 scribed have indicated a high ei'liciency; and the hand can be held upon the exhaust pipe '14 with-I out discomfort when the burneris in operation,"

thereby indicating Athat* most of the available ,4'0

heat *inthe burning gasesis imparted tothe water in the tank. w c 'Si l YI claimt:v 1. A waterjheater comprising a water storage. tank having a metal tube extended therethrough in free contactV pipe 'coil in said tube having rits ends inscommunicationfwith the 'top Vand bottom parts of the water'space'in the tank, a burner in combottom end offsaid tube, and adampe'r removably located in the upper end'of "said 'tube having means normally biasing it toward a closed position and means're. *s sponsive to the presence of a tube'for opening it, a removable support for said damper, and means providing a locating seat between said support and said tube` bywhich the position of-said damper withinssaid tube isv determined. l'. c .Y 2. A' water heater comprising a. water storageV tank having a vertical metal tube extending. therethroughin free contact` with the water in in communication with the tofp` and bottom vparts withfthe water in the tank, a

topY ofthe-shell is closed; 30v

damper Ycup are re-Y I Vof the water; space in the tank, Ya burner in corn- 'munieation with the bottoni endo: saidjtubdp and Vextended horrir,

centrically pivoted on said plate and overlying f and normally'closing said `opening and arranged'.V to pivot and uncover said openin'gin responseto the presence of Y a vheated gas 'insa'idtulznasaid plate and tube having cooperatniiiembersfprof the upper'endof Asaid tubef` and v ,Y

within said tube and defines the location of said damper.

3. A Water heater comprising a Water storage tank having a metal tube extended therethrough in free contact with the Water in the tank, a pipe coil in said tube having its ends in communication with the top and bottom parts of the vwater space in the tank, a burner in communication with the bottom end of said tube, a plate located Within the upper end of said tube and extended thereacross, means extended longitudinally of said tube and removably seated upon the top end thereof for supporting said plate removably in said tube, said plate having lan opening therethrough, and a damper pivotally connected with said plate and normally overlying said opening and seated on said plate, said damper being eccentrically pivoted and'having the parts on opposite sides of its pivotal axis so relatively .Weighted that said damper can pivot to an-open position in response to the presence of a heated gas in said tube.

4. A Water heater comprising a Water storage tank having a metal tube extendedtherethrough in free contact Withthe water in the tank, a'pipe coil in said tube having its ends in communication With the top and bottom parts of the Water space in the tank, a burner in communication with the bottom end of said tube, a damper cup located removably Within the open upper end of said tube and having a cylindrical sidewall, a bottom Wall provided with an openingtherethrough and an outstanding flange at the .to-p of said sidewall which overlies and is seated removably upon the top of said tube, and a damper plate eccentrical- 1y pivoted on said bottom wall and normally seated thereon and overlying said opening, said plate having unequal areas on opposite sides of its pivotal axis and being so- Weighted on opposite sides of its axis that it can swing to an open position in response to the presence of a heated gas in said tube. Y

5. A Water heater comprising awaterstorage tank having a metal tube extended therethrough in free contact with the Water in the tank, a pipe coil in said tube having its ends in communication with the top and bottom parts of the Water space in the tank, a burner in communication with the bottom end of said tubea damper cup Y located removably Within the open upper end of said tube and having a cylindrical side Wall, a bottom Wall provided with an opening therethrough and an outstanding ange at the top ofl said side wall which overlies and is seated removably upon the top of said tube, and a damper plate eccentrically pivoted on said bottom wall and normally seated thereon and overlying said opening, said plate having unequal areas on op- Vposite sides of its pivotal axis andY being so Weighted on opposite sides of its axis that it can swing to an open position in response to the presence of a heated gas in said tube, an open-ended cylindrical shell surrounding and extended above the top of said tube and having a lateral gas outlet, and a removable cover -on the open top of said shell, said damper cup being Aremovable through the open top of said shell.

6. A water heater comprising a water storage tank having a metal tube extended therethorugh in free contact with the Water in the tank, a pipe coil in said tube having itsv ends in communication with the top and bottom parts of the Water space in the tank, a burner in communication with the bottom end of said tube, a damper plate located removably within the top of said tube and having an opening therethrough, a damper pivoted on said plate and normally overlying and closing said opening and having parts of unequal area on opposite sides of its pivotal axis and being so Weighted on oppositeV sides of its axis that it can open in response to the presence of'a heated gas in said tube, an open ended shell surrounding and upstanding above the'open top of said tube and having a lateral gas outlet, and a removable cover on the open top of said shell, said daniper'plate and said damper thereon being removable thro-ugh the uncovered open top of said shell '7. A Water heater comprising a Water storage tank having a metal tube extended therethrough in free contact with the water in the tank, a pipe V coil in said tube having its ends in communication with the top and bottom parts of the Water space in the tank, a burner in communication with the bottom end of said tube, a heat-insulating cas-` ing enclosing said tank, the top of said tube being extended through the top of said casing, an open-ended shell surrounding and upstanding above the top of said tube and carried by said casing and having a lateral gas outlet, a removable cover on the open top of said shell, a damper Support located Within the open top end of said tube and under said cover, and a damper pivoted to said support and arranged to open automatically when said burner is in operation, said damper support being removably located Within said tube and being smaller than the open top of said shell Vso that it can be withdrawn therethrough when said cover is oir.

f OSCAR JOHNSON. 

